Opening the first meeting of Kennedy’s handpicked seven-member panel, committee chairman Martin Kulldorff said he was appointing a work group to evaluate the “cumulative effect” of the children’s vaccine schedule — the list of immunisations given at different times throughout childhood.

Also to be evaluated, he said, was how two other shots were administered — one that guards against liver-destroying hepatitis B and another that combines chickenpox protection with MMR, the measles, mumps and rubella vaccine.

It was an early sign of how the Advisory Committee on Immunisation Practices is being reshaped by Kennedy, a leading anti-vaccine activist before becoming the nation’s top health official.

He fired the entire 17-member panel this month and replaced it with a group that includes several anti-vaccine voices.

“Vaccines are not all good or bad,” Kulldorff said. “We are learning more about vaccines over time” and must “keep up to date.”

His announcement reflected a common message of vaccine skeptics: that too many shots may overwhelm kids’ immune systems or that the ingredients may build up to cause harm.

Scientists say those claims have been repeatedly investigated with no signs of concern.

Kids today are exposed to fewer antigens — immune-revving components — than their grandparents despite getting more doses, because of improved vaccine technology, said Dr Paul Offit, a vaccine expert at the Children’s Hospital of Philadelphia.

The American Academy of Paediatrics announced that it would continue publishing its own vaccine schedule for children but now would do so independently of the ACIP, calling it “no longer a credible process”.

“The narrative that current vaccine policies are flawed and need ‘fixing’ is a distortion,” said the AAP’s Dr Sean O’Leary.

“These policies have saved trillions of dollars and millions of lives.”

The ACIP, created more than 60 years ago, helps the Centres for Disease Control and Prevention determine who should be vaccinated against a long list of diseases, and when.

Those recommendations have a big impact on whether insurance covers vaccinations and where they’re available, such as at pharmacies.

After Kennedy’s abrupt dismissal of the existing expert panel, a number of the CDC’s top vaccine scientists — including some who lead the reporting of data and the vetting of presentations at ACIP meetings — have resigned or been moved out of previous positions.

And shortly before Wednesday’s meeting, a Virginia-based obstetrician and gynecologist appointed to the committee stepped down.

According to the Trump administration, he withdrew during a customary review of members’ financial holdings.

Scientists show data that COVID-19 vaccines protect pregnant women and kids

First on the committee’s agenda were COVID-19 vaccinations.

Kennedy already sidestepped the panel and announced the vaccine would no longer be recommended for healthy children or pregnant women.

Yet CDC scientists told the panel that vaccination was “the best protection” during pregnancy, and said most children hospitalised for COVID-19 over the past year were unvaccinated.

COVID-19 remains a public health threat, resulting in 32,000 to 51,000 US deaths and more than 250,000 hospitalisations since last fall, according to the CDC.

Most at risk for hospitalisation are seniors and children under two — especially infants under 6 months who could have some protection if their mother got vaccinated during pregnancy, according to the CDC’s presentation.

The new advisers weren’t asked to vote on Kennedy’s recommendations, which raise uncertainty about how easily people will be able to access COVID-19 vaccinations this fall.

After CDC staff outlined multiple overlapping systems that continue to track the vaccines’ safety, several advisers questioned if the real-world data really is trustworthy.

Committee will vote on RSV protections

Next, the committee took up RSV, or respiratory syncytial virus, a common cause of cold-like symptoms that can be dangerous for infants.

In 2023, US health officials began recommending two new measures to protect infants — a lab-made antibody for newborns and a vaccine for pregnant women — that experts say likely drove an improvement in infant mortality.

The committee will discuss another company’s newly approved antibody shot and vote on updated recommendations.

Flu shot recommendations to be debated

At its June meetings, the committee usually refreshes guidance for Americans 6 months and older to get a flu shot, and helps green light the annual fall vaccination campaign.

But a vote set for Thursday that also promises controversy.

The panel is set to consider a preservative in a subset of flu shots that Kennedy and some antivaccine groups have falsely contended is tied to autism.

In preparation, the CDC posted a new report confirming that research shows no link between the preservative, thimerosal, and autism or any other neurodevelopmental disorders.